4 PBGs bind to form HMB

Stable Identifier
R-HSA-189406
Type
Reaction [transition]
Species
Homo sapiens
Compartment
Synonyms
Four PBGs combine through deamination to form hydroxymethylbilane (HMB)
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Cytosolic porphobilinogen deaminase catalyzes the polymerization of four molecules of porphobilinogen (PBG) to generate hydroxymethylbilane (HMB), an unstable tetrapyrrole. This reaction is the first step in the formation of the tetrapyrrole macrocycle. Two isoforms of porphobilinogen deaminase are generated by alternative splicing, one expresssed in erythroid tissues and one ubiquitously expressed in the body. Deficiencies of both forms of PBG deaminase are associated with acute intermittent porphyria.

Literature References
Participants
Participant Of
Catalyst Activity
Catalyst Activity
Title
hydroxymethylbilane synthase activity of HMBS:DIPY [cytosol]
Physical Entity
Activity
Orthologous Events
Cross References
Rhea
Authored
Reviewed
Created